Recently, an image pickup device such as a digital camera is provided with an autofocus (hereinafter, referred to as an AF) function capable of performing a focusing operation automatically on a device side.
A lens-interchangeable single-lens reflex camera generally is configured so that AF control can be performed with a phase difference detection system. Further, a digital camera of a compact type generally is configured so that AF control uses a contrast detection system (which is a so-called hill climbing system and may be referred to as a “hill climbing system” in the following description) of moving a focusing lens to a focused position based on the contrast of an image. On the other hand, some types of recent lens interchangeable single-lens reflex cameras have a finder mode capable of recognizing an optical image visually with an optical finder and a live view mode of displaying an image (through image) being captured by an image pickup element on a liquid crystal monitor in real time. In such a configuration, AF control of a phase difference detection system is suitable for the finder mode since a mirror is placed down, while AF control of a hill climbing system is suitable for the live view mode since a mirror is placed up. Patent Document 1 discloses a configuration in which the system of the AF control is switched automatically in accordance with the switching of the finder mode/live view mode.    Patent Document 1: JP 2000-333064 A